The present invention relates to the iron and steel industry and, more particularly, to a method of melting solid iron in a gas cupola.
At present, when melting solid iron in a gas cupola a temperature exceeding the iron melting temperature is created in the cupola shaft, and then the cupola is charged with a burden consisting of solid iron and fluxes.
Charging of the above burden is carried out continuously which provides for a constant level of the burden to be maintained in the cupola.
The temperature required to conduct the iron melting operation is obtained due to the released heat of gases burnt in a gas burner arranged at the cupola shaft bottom.
Under the effect of the heat released by the gases, melting of the burden lower layer occurs, with the molten iron being continuously tapped from the cupola.
This well-known technique, however, has an essential disadvantage consisting in that at the end of the melting operation when the burden supply is stopped, at the cupola shaft bottom there appears a sow formed of metals and their oxides. This sow making up to 10 per cent of the solid iron charged is scrapped. Moreover, the sow hinders the gases passing into the cupola shaft which reduces the intensity of melting and decreases the cupola's productivity. Therefore, it is necessary to remove the sow when preparing the cupola for a next heat which results in damaging the refractory lining around the sow.